Musculoskeletal Research Unit, Translational Health Sciences, Bristol Medical School, University of Bristol, Learning and Research Building, Level 1, Southmead Hospital, Bristol, United Kingdom.
Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom.
PLoS One. 2022 Jun 29;17(6):e0270274. doi: 10.1371/journal.pone.0270274. eCollection 2022.
To assess the impact of local commissioners' policies for body mass index on access to knee replacement surgery in England.
A Natural Experimental Study using interrupted time series and difference-in-differences analysis. We used National Joint Registry for England data linked to the 2015 Index of Multiple Deprivation for 481,555 patients who had primary knee replacement surgery in England between January 2009 and December 2019. Clinical Commissioning Group policies introduced before June 2018 to alter access to knee replacement for patients who were overweight or obese were considered the intervention. The main outcome measures were rate per 100,000 of primary knee replacement surgery and patient demographics (body mass index, Index of Multiple Deprivation, independently-funded surgery) over time.
Rates of surgery had a sustained fall after the introduction of a policy (trend change of -0.98 operations per 100,000 population aged 40+, 95% confidence interval -1.22 to -0.74, P<0.001), whereas rates increased in localities with no policy introduction. At three years after introduction, there were 10.5 per 100,000 population fewer operations per quarter aged 40+ compared to the counterfactual, representing a fall of 14.1% from the rate expected had there been no change in trend. There was no dose response effect with policy severity. Rates of surgery fell in all patient groups, including non-obese patients following policy introduction. The proportion of independently-funded operations increased after policy introduction, as did the measure of socioeconomic deprivation of patients.
Body mass index policy introduction was associated with decreases in the rates of knee replacement surgery across localities that introduced policies. This affected all patient groups, not just obese patients at whom the policies were targeted. Changes in patient demographics seen after policy introduction suggest these policies may increase health inequalities and further qualitative research is needed to understand their implementation and impact.
评估英国地方委员会针对体重指数的政策对膝关节置换手术准入的影响。
使用自然实验研究，采用中断时间序列和差分法分析。我们使用英格兰国家联合登记处的数据，将其与 2015 年多因素贫困指数相关联，共纳入了 481555 名在 2009 年 1 月至 2019 年 12 月期间在英格兰接受初次膝关节置换手术的患者。考虑到 2018 年 6 月之前引入的改变超重或肥胖患者膝关节置换手术机会的临床委托组政策为干预措施。主要观察指标为每 10 万人中接受初次膝关节置换手术的比率和患者人口统计学特征（体重指数、多因素贫困指数、独立资助手术）随时间的变化。
在引入政策后，手术率持续下降（40 岁以上人群每 10 万人中手术减少 0.98 例，95%置信区间为-1.22 至-0.74，P<0.001），而在没有引入政策的地方，手术率则有所上升。引入政策三年后，与反事实相比，40 岁以上人群每季度的手术减少了 10.5 例/10 万人，相当于如果趋势没有变化，手术率将下降 14.1%。政策的严重程度与剂量反应无关。在政策引入后，所有患者群体的手术率都有所下降，包括非肥胖患者。政策引入后，独立资助手术的比例增加，患者的社会经济贫困程度也有所增加。
体重指数政策的引入与政策实施地区膝关节置换手术率的下降有关。这影响了所有患者群体，而不仅仅是针对肥胖患者的政策目标人群。政策引入后患者人口统计学特征的变化表明，这些政策可能会加剧健康不平等，需要进一步的定性研究来了解其实施和影响。
